Complementary Proteins

Complementary Proteins

Proteins are compounds made up of building blocks called “amino acids.” There are about 20 common amino acids. Nine of them are called “essential” because the body is unable make them, and so they must be supplied by the food you eat. If your diet does not contain enough of these essential amino acids, you will suffer the negative effects of protein deficiency.

Is it complete?

Foods that provide all of the essential amino acids are called “complete proteins." These complete protein foods generally come from animal sources. Plant foods do not, as a rule, have complete proteins, but by eating combinations of plant foods, called “complementary proteins,” you can obtain a complete protein.

For example, when you eat refried beans with rice, such as is often found in Mexican cuisine, you are obtaining a complete protein. The beans and rice complement each other, since each has some of the essential amino acids and when eaten together, you will have all of the essential amino acids.

It is generally believed by nutritionists that healthy eating does not require you to eat these foods at the same meal.

Animal or Vegetable, Generally Speaking

Complete Proteins = Animal proteins

Incomplete Proteins = Vegetable proteins

Here is a list of proteins that when eaten together become complete.

Here are some recipe ideas that combine the above-listed foods:

Lentil Soup

Split Pea Soup

Cottage Cheese - Walnut Loaf

Navy Bean Soup

Vegetarians and particularly, vegans need to be aware of the importance of the essential amino acids and getting complete proteins. Click on this link to learn more about vegetarian nutrition.

What does a serving of meatless protein look like?

For meatless protein sources, a serving, which is 1 large egg, 1/2 cup cooked beans or rice, or 2 Tablespoons of seeds, nuts or peanut butter, is equivalent to only about 1/3 of the protein in a serving of meat. Tofu is also in this group with a serving size of about 4 oz.

Fun Fact about Complementary Proteins:   A tiny grain called "quinoa" (pronounced keen-wah) is one of the few plant sources of complete protein. It comes in a red and a white variety and can be cooked to make a hot cereal or used in place of bulgur in some recipes.* It is also becoming more popular as an ingredient in wheat-free pastas. 

Quinoa recipe ideas: Use instead of bulgur in cold salads. Cook like oatmeal as a hot cereal or mix with oatmeal.  Boil 1 cup of quinoa in 2 cups water for about 15 minutes.

*Be sure to rinse the raw quinoa in cold water to remove any traces of the bitter coating on the seeds.  You can tell when the quinoa is cooked by looking for little curlicue tails that appear.

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